Note the aperture that image was taken with.
AA filters are not perfect. As I explained in the other thread you have responded to, they will pass higher spatial frequencies if the lens can reproduce them, which some good optics at low f/#s can achieve. So even with a strong AA filter, a good lens will STILL create aliasing - as your example demonstrates.
These arguments remind me of medieval philosophers debating how many angels can stand on the sharp end of a pin. Can an angel balance on a molecule, an atom, a proton, an electron, a gluon and so on?
A traditional AA filter is not a panacea against aliasing and moire - never has been and never will be. It helps, but it can never be perfect. However its "value" or usefulness degrades in proportion to pixel size because diffraction and lens aberrations create their own AA effect. Unlike the AA filter, both of these attenuate with spatial frequency so are, in that sense, self limiting.
Some day, not so far in the future, pixels will be so dense that no lens will be able to resolve individual pixels at any aperture and the AA filter will be, theoretically and practically, completely redundant. We are now in a transition phase, where taste and working aperture make some difference between what is preferable to any user.
I would rather control aliasing with choice of aperture - after all, we have evolved to see diffraction in our own eyes so it isn't objectionable - rather than have an engineer from another culture impose his ideal on me. But that depends on how well Canon have implemented the "compensation". Nikon didn't seem to achieve what was, in principle, possible and so they have decided to remove the AA filter entirely in response to user choice.
Then again there is the Pentax approach - and the potential for completely flexible, self limiting, AA filtering. Its not too difficult to see that being programmed to automatically adjust for the lens and its shooting aperture... ;-)
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Its RKM
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